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This work is an attempt to examine the wave propagation of thermally loaded graphene platelets (GPL)s reinforced nanocomposite plates. Particularly, an analytical approach is made to determine the extent of wave dispersion in functionally graded nanocomposite plates reinforced with graphene platelets (GPL)s when thermal loading is added to the structure. Along with thermal loading, the plate structure is rested on an elastic foundation to derive a more realistic outcome. Variety of thermal loads with different temperature rises have been studies in the present research; these loads include: uniform temperature rise (UTR), sinusoidal temperature rise (STR), and linear temperature rise (LTR). Moreover, the nanocomposite (NC) plate is rested on a Winkler–Pasternak elastic foundation. GPL particles are dispersed in the polymer base along the thickness of the plate in four differing distribution patterns. Furthermore, Hamilton's principle along with refined higher-order plate theory is utilized to derive the governing equations of the problem. Afterwards, these differential equations are solved in an analytical format to attain the wave frequency, as well as, the phase velocity of GPL-reinforced NC plate. Before, assessing the impact of numerous parameters on the wave propagation characteristics of GPL-reinforced NC plate, our analytical model had been validated with previous studies. Results of this study indicates that the wave dispersion of NC plates reinforced with GPLs is heavily depended on parameters such as GPL distribution pattern, thermal loading type, GPL weight fraction and so on. [ABSTRACT FROM AUTHOR]

Present research is mainly devoted to show the effects of temperature change on the mechanical properties of in-plane waves propagating in a single-layered graphene sheet. Graphene sheet is assumed to be rested on an elastic medium. Influences of elastic substrate on the behavior of graphene sheet is modeled by the means of a two parameter elastic foundation. In addition, a trigonometric refined plate theory is applied to derive the kinematic relations. Also, a nonlocal strain gradient theory is utilized to show the size-dependency of graphene sheet. In the framework of Hamilton's principle, the nonlocal governing differential equations are derived. Moreover, an analytical approach is applied to find the unknowns of the final eigen value equation. At the end of the paper, it is tried to clarify the influences of each parameter by the means of some diagrams. [ABSTRACT FROM AUTHOR]

In this research a nonlocal strain gradient plate model is introduced for hygro-thermo-mechanical buckling analysis of double-layered graphene sheets in elastic medium. For more accurate analysis of graphene sheets, the proposed theory contains two scale parameters related to the nonlocal and strain gradient effects. In fact, buckling load increment due to the strain gradient effect is neglected in all previous papers related to double-layer graphene sheets. Governing equations of a nonlocal strain gradient double-layer graphene sheet on elastic substrate are derived via Hamilton’s principle. Galerkin’s method is implemented to solve the governing equations for different boundary conditions. Effects of different factors such as hygro-thermal loading, nonlocal parameter, length scale parameter, elastic foundation, interlayer stiffness and boundary conditions on buckling characteristics a double-layer graphene sheet are studied. [ABSTRACT FROM AUTHOR]

This paper develops a nonlocal strain gradient plate model for damping vibration analysis of visco-elastically coupled double-layered graphene sheets. For more accurate analysis of graphene sheets, the proposed theory contains two scale parameters related to the nonlocal and strain gradient effects. In fact, frequency increment due to the strain gradient effect is neglected in all previous papers related to double-layer graphene sheets. Governing equations of a nonlocal strain gradient double-layer graphene sheet on elastic substrate are derived via Hamilton’s principle. Galerkin’s method is implemented to solve the governing equations for different boundary conditions. Effects of different factors such as damping coefficients, nonlocal parameter, length scale parameter, elastic foundation, interlayer stiffness and boundary conditions on vibration characteristics a double-layer graphene sheet are examined. [ABSTRACT FROM AUTHOR]

In the present article, the hygro-thermal wave propagation properties of single-layered graphene sheets (SLGSs) are investigated for the first time employing a nonlocal strain gradient theory. A refined higher-order two-variable plate theory is utilized to derive the kinematic relations of graphene sheets. Here, nonlocal strain gradient theory is used to achieve a more precise analysis of small-scale plates. In the framework of the Hamilton’s principle, the final governing equations are developed. Moreover, these obtained equations are deemed to be solved analytically and the wave frequency values are achieved. Some parametric studies are organized to investigate the influence of different variants such as nonlocal parameter, length scale parameter, wave number, temperature gradient and moisture concentration on the wave frequency of graphene sheets. [ABSTRACT FROM AUTHOR]